In the case of a known machine of this type (German Patent 17 57 361 B2), the kneading tools comprise two equally constructed hoops, the longitudinal axes of which are twisted helically. Due to the two meshing hoops, the dough is subjected to a kneading process, during which a change in direction is impressed on the dough passing through the kneading zone. The dough in the working area of the kneading tools experiences an acceleration and, as a result of folds being formed in opposite directions, is stretched. On leaving the working area, the dough collects in folds that are beaten together and compressed.